Conventionally, in the production of a semiconductor device, fine processing by lithography using a photoresist has been performed. The fine processing is a processing method of forming fine convexoconcave corresponding to the following pattern on the surface of a substrate by forming a thin film of a photoresist on a semiconductor substrate, such as silicon wafer; irradiating an activating light ray, such as an ultraviolet ray onto the resultant thin film through a mask pattern in which a pattern of a semiconductor device is depicted, to develop; and subjecting the substrate to etching processing using the resultant photoresist pattern as a protecting film.
Recently, the high integration of semiconductor devices is progressed and the activating light ray to be used tends to have a shorter wavelength, such as from a KrF excimer laser (248 nm) to an ArF excimer laser (193 nm). Following such a tendency, the influence of diffuse reflection of an activating light ray from the substrate or the influence of a standing wave has become a large problem. Thus, in order to solve this problem, widely studied is a method of providing a reflection preventing film (bottom anti-reflective coating) between the photoresist and the substrate. For such a reflection preventing film, many investigations on an organic reflection preventing film have been performed in terms of easiness of its use or the like (for example, see Patent Document 1).
Further, recently, for solving a problem of the wiring delay which has become apparent as the miniaturization of a pattern rule of the semiconductor device has progressed, it is studied to use copper as a wiring material. In addition, together with the study, a dual damascene process is studied as a wiring forming method for the semiconductor substrate. Then, in the dual damascene process, a via hole is formed and a reflection preventing film is formed to a substrate having a large aspect ratio. Therefore, for the reflection preventing film used in this process, filling characteristics capable of filling holes without voids, planarization characteristics capable of forming a planar film on the substrate surface, and the like are required. However, it is difficult to apply an organic material for a reflection preventing film to a substrate having a large aspect ratio and recently, materials focusing on the filling characteristics and the planarization characteristics have been developed (for example, see Patent Document 2, Patent Document 3, Patent Document 4 and Patent Document 5).
In addition, in the production of devices such as semiconductor devices, for reducing the poisoning effect of a photoresist by a dielectric layer, there is disclosed a method of providing a barrier layer formed from a composition containing crosslinkable polymers or the like between the dielectric layer and the photoresist (for example, Patent Document 6).
Thus, in the production of semiconductor devices in recent years, for achieving various effects besides the reflection preventing effect, as a layer between the semiconductor substrate and the photoresist, that is, as an underlayer of the photoresist, an organic underlayer film formed from a composition containing organic compounds has become disposed.
And now, these organic underlayer films are generally formed by applying an underlayer film forming composition on a semiconductor substrate and then by heating the semiconductor substrate at a high temperature of around 170 to 200° C. Therefore, there is such a problem that during heating at a high temperature, low molecular mass components contained in an underlayer film forming composition are volatilized or sublimated, and are attached to peripheral devices to contaminate the devices. In addition, there is also such a problem that the components attached to the devices fall onto a semiconductor substrate to adversely affect a pattern forming.
[Patent Document 1]
U.S. Pat. No. 5,919,599 Specification
[Patent Document 2]
Japanese Patent Application Publication No. JP-A-2000-294504
[Patent Document 3]
Japanese Patent Application Publication No. JP-A-2002-47430
[Patent Document 4]
Japanese Patent Application Publication No. JP-A-2002- 190519
[Patent Document 5]
Publication No. WO 02/05035 pamphlet
[Patent Document 6]
Japanese Patent Application Publication No. JP-A-2002-128847